// part1:C14:ex14.7.cpp
// class String.
#include <iostream>
class String
{
public:
    String();
    String(const char *str);
    friend ostream& operator<<(ostream &os, const String &str);
private:
    char *str;
};

ostream& operator<<(ostream &os, const String &str)
{
    cout << str;
    return os;
}
